Encyclopædia Britannica, Ninth Edition/Triton
TRITON.The genus Triton was constituted by Laurenti, in his Synopsis Reptilium, and the name was adopted by nearly all writers on Amphibia. In Brit. Mus. Cat.: Batrachia Gradientia, by G. A. Boulenger, the genus is expanded and called by the name Molge, which was used by Merrem in his Tentamen Syst. Amphibia, 1820. The genus belongs to the division Mecodonta of the family Salamandrida in Strauch's classification (see Amphibia, vol. i. p. 771). The definition of Molge given by Boulenger, which closely agrees with that of Triton adopted by Strauch, is as follows. Tongue free along the sides, adherent or somewhat free posteriorly. Palatine teeth in two straight or slightly curved series. Fronto-squamosal arch present (except in M. cristatus), ligamentous or bony. Toes five. Tail compressed. In Bell's British Reptiles, 2d ed., 1849, four species were described as occurring in Britain. According to Boulenger, there are only three British species, Molge cristata, Boul. (Laurenti), M. vulgaris, Boul. (Linn.), and M. palmata, Boul. (Schneider). We give a short account of these under the names Triton cristatus, T. vulgaris, and T. palmatus respectively.
The name Triton cristatus for the first species has been used by a great number of authoritative writers on Amphibia, including Laurenti, Tschudi, Bonaparte, Duméril and Bibron, and Strauch, and also by Bell and Fleming among students of British fauna.[1] The diagnosis of T. cristatus is as follows: The males have a dorsal crest which is toothed; the fronto-squamosal arch is absent; the colour of the ventral surface is orange with black spots. This species is commonly known as the great water-newt. The average length of the adult is 6 inches. The colours are most brilliant in the male, and more developed in the breeding season spring and summer than in winter. The back is blackish or yellowish brown, with round black spots; the sides of the tail are white. The dorsal crest of the male is separated entirely from the tail crest, and both disappear in winter. The skin is covered with warty tubercles. There are no parotids; but glandular pores are present over the eyes and in a longitudinal series along each side. The species is pretty common in ponds and ditches in most parts of Britain, but more abundant in the south than in the north; in the neighbourhood of London it is found in great numbers. Its food consists of aquatic insects and other small animals; in the spring it devours the young tadpoles of the frog with avidity, and occasionally it feeds on the smaller species, T. vulgaris. In winter it hibernates, either quitting the water and hiding under stones or remaining torpid at the bottom of the water. It breeds chiefly in May and June. As in all Salamandrida, a true copulation takes place and the fertilization of the ova is internal. The female deposits each egg separately in the fold of a leaf, which she bends by means of her hind feet; the adhesive slime surrounding the vitellus keeps the leaf folded. The tadpole when first hatched is much more fish-like in form than that of the frog, the body diminishing in thickness gradually to the end of the tail. A continuous median fin runs along the back from the head, round the end of the tail, along the ventral median line, to the region of the gills, thus extending, as in many fish larvae, in front of the anus. The larva possesses three pairs of branched external gills, and in front of these a pair of processes by which it can adhere to fixed objects in the water. T. cristatus is abundant throughout Europe, ranging from Sweden and Russia southwards to Greece, and from Britain to the Caucasus.
The diagnosis of T. vulgaris, the Lissotriton punctatus of Bell, is:—Males with a dorsal crest continuous with the caudal, and festooned; belly not brilliantly coloured; back spotted. This species, often called the common or small newt, has a smooth skin, no glandular pores on the sides, but two patches on the head. It is as abundant in Britain as the former, or more so, but differs somewhat in habits, in autumn and winter being almost entirely terrestrial, and only living in water during the breeding season. Like the former species it is carnivorous. It is found in most parts of Britain, and throughout Europe, except in the south of France, Spain, and Portugal; it also extends into temperate Asia.
T. palmatus Tschudi (Schneider), the Lissotriton palmipes of Bell, is thus distinguished:—Male with dorsal crest, which is low with an even margin and continuous with the caudal; fronto-squamosal arch long; toes in male webbed. Other less distinctive features are that the back is flattened, with a raised line on each side, and the tail in the male truncate, terminating in a short slender filament. This species is not so common in Britain as the other two; it is widely distributed throughout Europe. It was first discovered in Britain in 1843. Boulenger recognizes nineteen species of Molge, of which nine besides those found in Britain are European. Only two species occur in America. Strauch gives twenty species.
- ↑ The species of Triton are called in English efts, evets, or newts.